What is the least common multiple of 20 and 5? Another way to say this is: $\lcm(20, 5) = {?}$
Solution: The least common multiple is the smallest number that is a multiple of 20 and 5. We know that 20 x 5 (or 100) is a common multiple, but is it the least common multiple? Write out the multiples of 20 until we find a number divisible by 5. 20, So, 20 is the least common multiple of 20 and 5.